We develop a theoretical model involving religiosity [intrinsic (I), extrinsic-social (E s), and extrinsic-personal (E p), Time 1], Machiavellianism (Time 2), and propensity to engage in unethical behavior (Time 2) to investigate direct and indirect paths. We collected two-wave panel data from 359 students who had some work experiences. For the whole sample, intrinsic religiosity (I) indirectly curbed unethical intentions through the absence of Machiavellianism, the bright side of religiosity. Both extrinsic-social (E s) and extrinsic-personal (E p) directly, while extrinsic-social (E s) indirectly, exacerbated unethical intentions, the dark side of religiosity. Multiple-group analyses across gender, college major, and income showed that the bright side existed directly for low-income students, but indirectly for males and females, business majors, and low-income students. Our novel finding showed that E p undermined unethical intentions indirectly for females. For the dark side, E s incited unethical intentions directly for males, business students, and low-income individuals, but indirectly for females, psychology majors, and low-income people. The Machiavellianism–unethical intentions relationship was the strongest for high-income participants. Religiosity had the highest number of significant paths for low-income individuals and the strongest dark side for males and high-income students, but the highest bright outcome for females. Our novel, original findings foster theory development and testing, add new vocabulary to the conversation of religiosity and unethical intentions, and improve practice